A new study finds that children with immigrant fathers are much more likely to suffer from post-traumatic stress disorder (PTSD).

The register-based study, conducted by researchers from the University of Turku in Finland, included 3,639 children born in Finland between 1987-2012 who were diagnosed with PTSD.

The findings show that children who had an immigrant father were twice as likely be diagnosed with PTSD than those with two Finnish parents. The researchers stress that schools and clinicians should become more aware of the intergenerational transmission of trauma.

PTSD is a trauma-and stressor-related disorder that can occur when a person experiences a traumatic event. Individuals with PTSD develop symptoms such as re-experiencing the traumatic event, avoidance of stimuli, negative alterations in cognition and moods, and hyperarousal.

“In this population-based study we showed that if children’s fathers had migrated less than five years before the birth of their child, the risk for PTSD diagnosis in children was almost twofold,” said doctoral candidate Sanju Silwal from the Research Centre for Child Psychiatry at the University of Turku, and the main author of the paper.

The study also reveals that the risk for a PTSD diagnosis is two times higher among kids with immigrant fathers born in North Africa or the Middle East.

“The finding is likely to be related to the fact that immigrants from that part of the world are often entering Finland as refugees. The whole immigration process for them may be a traumatic experience as it usually involves various burdening experiences during the trip, and even after arrival to the host country, it may take years before receiving the asylum decision,” Silwal said.

According to Silwal, it is important to note that the study involved a heterogeneous group of immigrants, and refugees could not be distinguished from others who migrated to Finland for study, work or family ties.

Dr. Andre Sourander, a professor of child psychiatry from the University of Turku, says there is increasing evidence of intergenerational transmission of trauma among holocaust survivors, veterans and refugees.

“Moreover, parental traumatization might impair parenting capacities and attachment relationship with their children and increase the risk of traumatic events in the family,” Sourander said.

The findings are significant for both clinical practice and research, said Silwal. “If left untreated, traumatic events can increase the risk for other psychiatric disorders and cause serious disability and chronic illness such as depression and cardiovascular diseases,” she said.

It is important that clinicians who treat traumatized immigrant parents are aware of the possible trauma transmission in their children. Schools and clinicians need to pay more attention to understand the cultural contexts and behavioral problems of immigrant children, to which the trauma exposure may impact, researchers stressed.

“With the increasing immigrant population in Europe, studies on PTSD among second generation immigrants are of great importance,” Silwal said.